Rotors of dynamoelectric machines, especially of electric motors, are subjected in practice to a large number of requirements, some of which are in conflict with one another. The most important of such requirements applicable to rotors of the type mentioned in the introduction or to the dynamoelectric machines equipped therewith are high efficiency, high power, compact construction, reliability and longevity, low time and effort for maintenance, low producing costs, light weight and low mass moments of inertia. These requirements apply in particular for electric starters of internal combustion engines, wherein new challenges, particularly with regard to the life expectancy of the starter in question, have transpired because of the intensified use of start/stop functions of the motor vehicles equipped with such internal combustion engines.
The object of the present invention is to provide a rotor mentioned in the introduction that in the sense of a particularly practical compromise with regard to the requirements relevant to practice explained in the foregoing is characterized by particularly high practicality, especially also with regard to the use thereof in starters of internal combustion engines.